524 PROCEEDINGS OP THE AMERICAN ACADEMY 



the two varieties of carbon, black and gray, using as a standard the 

 acetylene flame, have been made up to temperatures above 1600°. I 

 am at present struggling with the more difficult range between 1600° 

 and the melting point of platinum. The determination of the higher 

 temperatures offers consideraljle difficulty as yet, but there are indi- 

 cations which make it seem worth while to carry the investigation to 

 as high a point as possible. The research involves three subordinate 

 investigations, one of which, on the temperatures of the acetylene flame 

 itself, is completed. This I have made the subject of a paper read be- 

 fore the Physical Society. It is likewise printed in the April number 

 of the Physical Review. In my report to the American Academy, I 

 shall incorporate the results of these measurements in connection with 

 the main subject. Of the other two subordinate researches, the study 

 of the thermo elements employed is nearly completed, and a determina- 

 tion of the distribution of energy in the spectrum of the acetylene flame 

 by means of the Nichols radiometer is in progress. The latter is being 

 carried on by one of my assistants, Mr. G. W. Stewart, and we hope 

 as a result of his measurements to obtain a study of the absolute values, 

 by means of which spectrophotometric measurements for different wave 

 lengths can be brouarht into known relations to each other. 



" The work for which the grant was made from the Rumford Fund 

 has required a much longer time than I anticipated, but in spite of the 

 numerous difficulties which we have had to overcome, I think the end 

 is now in sight." 



PROFESSOR EDWARD C. PICKERING. 



Grant of January 10, 1900, $500 for the purpose of carrying out an 

 investigation on the Brightness of Faint Stars, by cooperation with cer- 

 tain observatories possessing large telescopes. 



" An appropriation of five hundred dollars ($500) has been made 

 from the Rumford Fund, to be expended under the direction of Pro- 

 fessor Pickering, for the purpose of carrying out an investigation on the 

 brightness of faint stars by cooperation with certain observatories possess- 

 ing large telescopes. This appropriation results from a communication 

 made to the Council of the American Astronomical and Astro-physical 

 Society held in New York last January. It was represented that the 

 most urgent need of astronomy in America was adequate endowment 

 of the great telescopes of the country so that they could be kept actively 

 at work. It was shown that while tlie two largest telescopes of the 

 country, and of the world, were kept constantly at work, the means for 



